The Parker Story volume 2 has a table in the appendix with the serial numbers of the 11 gauge shotguns taken from the records. There are 161 listed. Your serial number isn't in the list, but 3521, is. If the records show one only 8 numbers off they should show what yours is chambered for. I don't know how complete the list is.

Parker 3529 is shown as a 10-gauge in the serialization book.





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